EXPRESSION OF TUMOR-NECROSIS-FACTOR-ALPHA AND ITS RECEPTORS TYPE-I AND TYPE-II IN HUMAN OOCYTES

The present study was conducted to examine the expression of tumor nec rosis factor-alpha (TNF-alpha) and its receptors (types I and II, desi gnated TNFR-I and TNFR-II, respectively) in human oocytes and cumulus cells at the mRNA and protein levels, mRNA expression was investigated using a reverse transcriptase-polymerase chain reaction (PCR)/Souther n hybridization procedure. DNA-free RNA was isolated from the oocytes/ cumulus cells, reverse-transcribed, and PCR-amplified using specific o ligonucleotide primers based upon genomic/cDNA sequences. The expected bands of 303 bp and 513 bp were observed in oocytes and cumulus cells using primers based on genomic/cDNA sequences of TNF-alpha and TNFR-I I, respectively, that hybridized with specific cDNA probes in Southern blot hybridization procedure. The expected band of 368 bp was not obs erved in oocytes and cumulus cells using primers based on the TNFR-I c DNA sequence. Similar results were observed for expression at the prot ein level, as seen by the immunoreactivity of the specific antibodies with the paraformaldehyde-fixed oocytes and cumulus cells in the indir ect immunofluorescence technique (IFT). These results indicate that hu man oocytes and cumulus cells express TNF-alpha and its receptor type II (TNFR-II), and not type I (TNFR-I), both at the mRNA and protein le vels. These findings provide further evidence and substantiate the pro posed physiologic role of TNF-alpha in ovarian function, and may lead to clinical applications in in vitro fertilization programs and in dia gnosis and treatment of infertility in women, especially in cases attr ibuted to ovarian dysfunction. (C) 1997 Wiley-Liss, Inc.